"This policy extends to digital media buyers at all GroupM agencies, as well as other WPP companies like Team Detroit, which manages Ford's media business."

All publishers that want to carry advertising with GroupM will have to sign up to its new anti-piracy policy.

GroupM's own content producing clients – such as Warner Bros, Paramount, Universal Music and Summit Entertainment, which produced the popular Twilight series of vampire movies – have shared their own lists of pirate websites to help create a master copy.

"Pirate sites are known to 'domain hop,' so we need to keep on top of the latest list of identified offenders as best as we possibly can in order to enforce this new policy to its fullest effect," said Norman.

GroupM serves as the parent company and central buying point for WPP media agencies including Maxus, MEC, MediaCom, and Mindshare.

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